Water Pump Oil Leak Issues....

[Desert_75]

Hello all, appreciate the info on this board. 1975 GT750

I removed the water pump (luckily it came out pretty easily) and found that both O-Rings (pictured) were tore up pretty bad, so I replaced them. Oil was slowly dripping out of the weep hole after short rides so, after reading up on this board, assumed this was the cause.

I ordered the 2 o-rings from bike bandit utilizing the stock part numbers, lubed them, slid the water pump back up in until I found the notch and gently tapped it back in. Circlipped it and everything looked great!

I rode the bike around for about half an hour to get the motor hot and no drips.... success! Until the other night, spent about an hour on the bike, parked it still no leaks. Woke up the next morning and a puddle of oil under the bike the size of a dollar bill, and dripping from the weep hole again.

Did I do something wrong here? I didn't disassemble the water pump (largely because I couldn't figure out how) but I did order #10 as well, and still have it. Maybe an O-Ring failed or got pinched when I slid it back up in there? Guess I'll be pulling it apart again.....

[tz375]

It's possible that the top O ring was scratched on asse3mbly and has failed or the oil seal inside the pump is shot.

The whole pump needs to be stripped out and rebuilt or replaced. If you can do that yourself, you can save some cash, or just buy a new pump and slip it in.

[Desert_75]

That's what I was fearing. I noticed a pin (#17) in there that looks like it needed to be pressed out, then I assume the whole assembly will come apart??? I have new pipes coming in this week, guess now's a better time then ever.... Appreciate the response.

The pump and impeller are in great shape, no way I'm scrapping it without a valiant effort!

[tz375]

That's what I was fearing. I noticed a pin (#17) in there that looks like it needed to be pressed out, then I assume the whole assembly will come apart??? I have new pipes coming in this week, guess now's a better time then ever.... Appreciate the response.

The pump and impeller are in great shape, no way I'm scrapping it without a valiant effort!

#17 is a roll pin which is a hollow spring pin and it comes out quite easily and then runs under the bench and hides. On older pumps the impeller is located with a woodruff key.

That seal is not uncommon and your local seal shop should be able to get one for you. The graphite seal is not so easy to find and the stainless seat is even harder to find in good condition. The worst problem I find are corroded shafts that are beyond repair, scored shafts that leak, grooved steel seats, cracked graphite seals and impellers and shafts damaged by the use of vice grips etc. I use the pin and a couple of tire irons to gently lever the pump out with the bike lying on a pile of blankets on its side with tanks and side covers put somewhere safe.

[Desert_75]

When I pull it again I'll post up pics for you all to critique. Thanks. From what I remember there wasn't a lot of corrosion, I'll check again. Maybe I rolled the o-ring off the groove and didn't know it. Weird though, it ran great, no leaks for a while, then let loose.

[Desert_75]

Just to update, took the bike out for an hour last night, no leaks. Strange to say the least.... Maybe the leak was somewhere else and running over the weep hole. Maybe the case was overfilled (I removed the screw until it bled out).